Microlenses are used primarily for devices which require an optical focusing apparatus, such as for example cameras of mobile phones. As a result of pressure to miniaturize, the functional areas are becoming smaller and smaller. The more microlenses are to be miniaturized, the more difficult their optically correct production becomes, because at the same time, there is enormous cost pressure for the microlenses which are ideally to be manufactured in mass production. In the prior art, microlenses are produced on a carrier substrate by different production methods, such as shown for example in U.S. Pat. No. 6,846,137 B1, U.S. Pat. No. 5,324,623, U.S. Pat. No. 5,853,960 and U.S. Pat. No. 5,871,888. It is common to all the aforementioned methods that, dictated by principle, a certain thickness is necessary and the light which passes through the microlens must pass not only through the lens, but the carrier substrate. Due to the simultaneously required high quality and demands for higher resolution with simultaneously higher brilliance which depends, among other items, on the thickness and the number of optics along the optical axis, therefore the beam path, further optimization of the microlenses is desirable.
The fidelity of shape of a microlens is especially important. This is defined as the microlens having to be the exact negative of the die. Very often the fidelity of shape of a microlens during the curing process of the microlens is not maintained since the microlens shrinks, and therefore a differential volume arises between the die and the microlens.
Another important property of a good microlens is the optical axis. The elimination of a wedge fault of the die relative to the carrier is especially important for a correct optical axis of the microlens, since in the presence of the wedge fault during embossing, the optical axis cannot be embossed exactly perpendicular to the carrier.